This invention relates to an improvement in a balance having a digital display, with a measuring device producing measured values continuously, and in which the measured values are transferred to the display at a present frequency.
In conventional balances with optical projection and display of a scale, an operator cannor read the display while the balance is moving. The magnified numbers in the display, produced on a transparent screen, appear on this screen as changing, blurred shadows, from which the displayed measured value cannot be deciphered. Hence, addition of material being weighted must be interrupted occasionally to allow the balance to assume a resting position and to permit the displayed measured value to be read exactly. This is time consuming.
Hence, it is known from Swiss Patent 213,453 to provide mechanical balances with optical projection with an additional mechanical readout as a monitoring display and weighing accessory circuit; alternatively, a special marking can be provided on the projected scale, for example, a diagonal line as known Swiss Patent 365,554. In this way, at least a rough indication of the measured value at a given moment can be determined during weighing, in other words, when the displayed measured value is changing rapidly.
It is also known from the German Utility Model 6,901,976 to provide in mechanical balances a digital monitoring display by using a suitable grid.
A particular disadvantage of these mechanical and analog displays is the inertia of the indicator, which results in overshooting the measurement point. In addition, two separate displays are required, thus increasing the design and construction cost.
Furthermore, it is known from the German Utility Model 6,806,498 to provide an analog display with low resolution as a weighing accessory for electronic balances in addition to the digital display. This allows the magnitude and direction of the change in the measured value to be recognized more easily, so that adjustment or compensation of a measured value is facilitated.
Finally, a display has been proposed for a monitoring readout on a balance, wherein a display element is provided which is a schematic respresentation of the weighing system design which is optically visible, taking the form of a relatively long narrow glowing strip, whereby the design of the weighing system is illustrated by the geometric shape of the strip.
A disadvantage of this use of an additional analog display in addition to the digital display for electronic balances is again the fact that two separate and separately controllable displays must be provided. Moreover, the analog display has insufficient accuracy, since only 10 to 100 increments can be shown on the strip by contrast with 10.sup.4 and 10.sup.6 increments for a digital display.